Abstract
This work studies the functioning of the power system, taking into account renewable energy sources (RES) in the generation structure in terms of power balance and voltage maintenance. We consider a mathematical model of the functioning of the power system with a solar power plant (SPP) based on a simplified Kazakh power grid and investigate the problem of its control at the maximum power capacity of SPP. Within the framework of the model we give an example where the operational control of the power system by means of reactive power of capacitor banks allows us to increase the maximum power of the SPP compared to deterministic methods of power system control, but it excludes from consideration some unlikely scenarios of its active generation. The results show that with the integration of large RES plants there is a need to refine the existing centralized power system control system in the form of intelligent tools for managing reactive power flows, associated with a probabilistic description of generation and forecasting of RES.